Processing Excel Files

Processing Excel Files

Edit and manipulate Excel files using the xlsx-populate library while perfectly preserving original formatting.

When to Use

• User wants to edit existing Excel files without destroying formatting
• Working with .xlsx files that have complex layouts or merged cells
• Need to add formulas, styling, or new worksheets to existing files
• Creating Excel reports from templates

When NOT to Use

• Only need to read data from Excel (use xlsx library instead for better performance)
• Creating simple Excel files from scratch without formatting concerns

Quick Start

const XlsxPopulate = require('xlsx-populate');

// Load and edit
const workbook = await XlsxPopulate.fromFileAsync('input.xlsx');
workbook.sheet(0).cell('A1').value('Updated');
await workbook.toFileAsync('output.xlsx');

Installation

npm install xlsx-populate

Core Operations

1. Load and Preserve Formatting

const workbook = await XlsxPopulate.fromFileAsync('file.xlsx');
const sheet = workbook.sheet(0);